Learning to love and appreciate her body has been a long and difficult struggle for Lily Collins. Now, the actress, who's been honest about her past struggles with an eating disorder, will portray a young woman undergoing inpatient treatment for anorexia in the Netflix film, To the Bone, out later this month.

While it was her personal history that in part drew her to the first-of-its-kind role, it also required her to lose a lot of weight-something that was understandably scary for the actress. "I was terrified that doing the movie would take me backward, but I had to remind myself that they hired me to tell a story, not to be a certain weight," she shared in our July/August issue. "In the end, it was a gift to be able to step back into shoes I had once worn but from a more mature place."

Given her past, Collins knew the importance of this issue, but she came to some surprising realizations during the filming process. One big one? We need to stop glorifying "skinny" at all costs; she was praised for losing weight for the role.

"I was leaving my apartment one day and someone I've known for a long time, my mom's age, said to me, 'Oh, wow, look at you!'" Collins told The Edit. "I tried to explain [I lost weight for a role] and she goes, 'No! I want to know what you're doing, you look great!' I got into the car with my mom and said, 'That is why the problem exists.'"

And while she was praised on one end for looking great, she revealed that the weight loss the movie required also affected her career, with magazines refusing to photograph her for shoots because she was too skinny at the time of filming. "I told my publicist that if I could snap my fingers and gain 10 pounds right that second, I would," she said.

Still, Collins shared in the interview that she wouldn't trade the opportunity to bring necessary attention to an issue that affects one in three women-yet is still considered so taboo. (To the Bone is the first known feature film about a person with an eating disorder.)

Today, Collins has done a complete 180 and has changed her definition of healthy. "I used to see healthy as this image of what I thought perfect looked like-the perfect muscle definition, etc.," she tells Shape. "But healthy now is how strong I feel. It's a beautiful change because if you're strong and confident, it doesn't matter what muscles are showing. Today I love my shape. My body is the shape it is because it holds my heart."